528  Nose Gear Manual Extension Release Mechanism Installation 
Jun 20/90  Figure 401 (Sheet 2) BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  32-35-21 Page 403 

3. Install Nose Gear Manual Extension System Cables
A.  Install system cables. For general installation information to be used in conjunction with the following steps, refer to Control Cables, Chapter 20.
NOTE:  See figure 401 for cable lengths and fittings.
B.  Install rigging pin (4) through torque tube pulley (7) and bracket assembly (10). (See view 1.)
C.  Attach cable MNGEA on torque tube pulley (7) and install cotter pin.
D.  Attach cables MNGEA on control drum (3) and install cable retainer.
E.  Feed terminal end of manual extension handle cable through hole in V-slot and attach cable on control drum (3) and install cotter pin. Bend one end of cotter pin into end of drum.
F.  Connect cable MNGEA at turnbuckle. (See view 2.)
G.  Rig cable to 100 pound rig load.
NOTE:  When performing step G., check that release handle is properly seated in V-slot of manual extension control. (See detail A.)
H.  Connect return spring to torque tube quadrant (7).
I.  Adjust manual extension system per 32-35-0.
J.  Test manual extension system per 32-35-0.
K.  Install pressure seal (8) in nose gear wheel well ceiling. (See view 1.)
L.  Install cabin floor panel (12).
500 
32-35-21 Page 404  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  Feb 15/68 

WHEELS AND BRAKES - DESCRIPTION
1.  General
A.  The airplane is supported during landing, takeoff, and ground operations on six wheel and tubeless tire assemblies. Four are on the main landing gear and two on the nose landing gear. Each main wheel is provided with a brake unit bolted to a flange on the axle. The brakes are multiple disc type, with stationary carrier and divided lining discs, and segmented rotating brake discs. Each brake is provided with pistons, which actuate the brakes when hydraulic pressure is applied. The brakes are also provided with combination return springs and automatic adjusters. The automatic adjusters compensate for brake wear.
B.  To provide ground braking capability and to stop spinning wheels after takeoff, two braking systems are provided.
(1)  
A hydraulic brake system is the normal braking system and is controlled by the captain's or first officer's rudder pedals through linkage and cables to the brake metering valve for each main landing gear. Each brake metering valve serves a dual purpose and directs A system hydraulic pressure to the inboard brake and B system hydraulic pressure to the outboard brake of its gear.

(2)  
A parking brake system provides braking while the airplane is parked or moored. It is controlled by a handle on the control stand. The parking brake linkage holds the brake pedals in the brake applied position and a linkage actuated switch closes the parking shutoff valve in the common return line from the antiskid valves.

C.  An antiskid system assumes automatic control of brake pressure through the antiskid valves. The antiskid system is normally on with the on-off switch on the pilots' aisle stand.
500 
Apr 15/66  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  32-40-0 Page 1 

HYDRAULIC BRAKE SYSTEM - DESCRIPTION AND OPERATION
1. General
A.  The hydraulic braking system aids airplane control during ground operations. Brakes hold the airplane during parking, mooring, and engine run; stop spinning wheels after takeoff; shorten the landing run; and assist in turning when the airplane is taxied.
B.  The brake system is manually controlled by the captain's or first officer's rudder pedals through linkage and cables to the brake metering valve for each main gear. Each brake metering valve serves a dual purpose as it directs system A hydraulic pressure up to 3000 psi to the inboard brake and system B hydraulic pressure up to 3000 psi to the outboard brake of the main gear it serves. An antiskid system and an automatic braking system are incorporated into the manual braking system. (Ref 32-42-0, Antiskid System - Description and Operation; and 32-43-0, Automatic Braking System - Description and Operation.)
C.  The brake system consists of dual cables and linkage, dual metering valves, brake valve feel augmentation actuators, main gear brake swivels, disk-type brakes, hydraulic pressure accumulators, transmitters and gages (Fig. 1) . A parking brake shutoff valve, covered in 32-44-0, and an antiskid control valve, covered in 32-42-0, are mentioned in the operation of the brake system, but are considered components of the parking brake system and the antiskid system, respectively. Automatic braking system components, an autobrake control valve module, two pressure switches, and a fuse are installed in the brake hydraulic system. These components are mentioned in operation of the brake system, but are part of the automatic braking system and are covered in 32-43-0. The brake valve feel augmentation actuators provide increased brake pedal resistance at low braking pressure without increasing the pedal resistance at maximum braking pressure. The brakes are of the rotating disk type and are self-adjusting. The hydraulic pressure accumulators are charged to 1000 psi to provide braking pressure for parking or whenever the main hydraulic systems are depressurized. The hydraulic pressure transmitter provides a brake system hydraulic pressure indication on a remote gage in the control cabin. The brakes are applied automatically to stop the spinning main gear wheels when the landing gear is retracted. A snubber is provided in the nose wheel well to stop the spinning nose wheels (Ref 32-45-0). A ground interconnect valve allows pressurization of all brakes from B system hydraulic pressure. The valve is controlled by a switch on the overhead panel (P5) and can be opened only when the parking brake is set.
　
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